题目内容：
Microblogging(微博)appearedin2006andhasmovedfromitsearly,perceivedlimitationstogrowinpopularityandbecomeapowerfulplatformforsharingusefulinformationandknowledge．51．Thereareover100microbloggingservicesinoperation,withsomeofthebetter-knownservicesbeingTwitter,PlurkandTumblr． 52．Theoriginaluseformicrobloggingwastoallowpeopletobroadcastwhattheyweredoingatanypointintime,forexample"HavingcoffeewithJane"or"Caughtintrafficonmywaytowork"．Althoughthisisstillamajoruseformicroblogging,ithasdevelopedintoamuchmorecomplexarrayofcommunications．Peopleusemicrobloggingplatformstoshareandseekinformationbutin140-200characters．
53．Thismaybeintheformofbroadcastingwhattheyarethinking;askingforsupportoradvice;sharingresources;ordiscussionwithothers．
54．Microblogging,andotherformsofsocialmedia,havehadanimpactasprofoundastheprintingpress．Theprintingpresschangeddistributionof,andaccessto,informationforalltime,givingwidespreadaccesstoinformationthatwaspreviouslyunavailabletothemajorityofthepopulation．OncepeoplehadthisaccesstheydemandedmoreandwehaveseenthisthirstforinformationeversinceMicrobloggingapplicationshaveextendedthisaccessevenfurtherbyenablingpeopletocreateanddistributeinformationasopposedtobeingjustconsumersofinformationthatisdistributedand"controlled"byothers．
Itisimportanttounderstandhowandwhymicrobloggingisbeingused．55．Thisunderstandingwillenableustofurtherdevelopandenhancemicrobloggingtoolsintousefulcollaborativespaces．
第（51）题答案
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